Increases in internal Ca2+ and decreases in internal H+ are induced by general anesthetics in squid axons
Autor: | L.J. Mullins, J. Whittembury, G. Vassort |
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Rok vydání: | 1986 |
Předmět: |
Microinjections
Arsenazo III Biophysics chemistry.chemical_element Calcium law.invention Absorbance 03 medical and health sciences chemistry.chemical_compound 0302 clinical medicine law biology.animal Animals 030304 developmental biology Anesthetics Phenol red 0303 health sciences Squid biology Chemistry Decapodiformes Metabolism Hydrogen-Ion Concentration Glass electrode Axons Saturation (chemistry) 030217 neurology & neurosurgery Research Article |
Zdroj: | Biophysical journal. 50(1) |
ISSN: | 0006-3495 |
Popis: | Squid axons were injected with arsenazo III and treated with sea water containing compounds usually classified as general anesthetics, (pentanol-decanol and a variety of hydrocarbons and their derivatives). Such treatment led to an increase in absorbance by arsenazo III at wavelengths sensitive to [Ca]i. The effect was independent of the presence or absence of Ca++ in sea water and it was not modified by substances that release Ca from internal stores. The effect was easily reversible. In axons injected with phenol red or impaled with a glass electrode sensitive to H+, a similar treatment led to an alkalinization that was also readily reversible. Both Ca release and the change to an alkaline pH had identical time courses. The dose required for action by all of the chemical agents studied could be predicted from a knowledge of their fractional saturation in sea water, i.e. from their thermodynamic activity. For compounds with 8–10 carbon atoms, Ca-release effects can occur at concentration less than those necessary to block either conduction or Na/Ca exchange. A special chemical agent was octylamine, which induced a marked rise in pHi and in addition its nonionic form produced the typical Ca release associated with general anesthetics. |
Databáze: | OpenAIRE |
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